JPH0747923A - Seat belt retractor - Google Patents

Abstract

PURPOSE: To maintain the function of a locking mechanism without damaging a blocked control disk by providing an energy conversion device. CONSTITUTION: This seat belt retractor has a belt reel 12 rotatably mounted in a frame 10 and a latching mechanism which is sensitive to any abnormalities in the running condition of an automobile has a control disk connected to the belt reel 12. A belt tensioning device engages the first axial end of a torsion bar 30, the second end of which is drivingly coupled to the belt reel. After belt tensioning the first axial end of the torsion bar 30 is blocked on the frame 10. When a load is exerted via a belt web 14, the torsion bar 30 is twisted for conversion of energy. The control disk is connected to the belt reel 12 via torque-limiting couplings 60, 62.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a seat belt retractor having a belt pretension drive which engages a belt reel mounted rotatably in a frame.

[0002]

BACKGROUND OF THE INVENTION In a belt retractor of the type known from U.S. Pat. No. 4,423,846, a belt reel is provided after belt tension or belt tension. tensi
After tightening the clamping roller, the belt reel is blocked by a coupling mechanism that rigidly connects the belt reel to the tensioning drive, which is further locked by the locking roller when the tensioning process is completed. Attempts have already been made to enhance protection by means of a seat belt device with a belt tensioner by converting energy after belt tensioning and reducing the peak load on the belt web or belt. . Converting energy in this way is possible, for example, by means of a stretcher member incorporated into the positive interlock of the belt device which plastically deforms when a load is applied.

[0003]

SUMMARY OF THE INVENTION In accordance with the present invention, there is provided a novel belt retractor having a belt pretension drive incorporating an energy conversion device. According to the present invention, the seat belt retractor includes a frame, a belt reel rotatably supported in the frame, a belt winding or winding direction.
and a belt pre-tension drive device for rotating the belt reel. The torsion bar has a first shaft end connected to the belt reel and a second shaft end engaged by the belt pretension drive. The locking device is configured such that, after the belt pretension drive device is actuated, the belt is unloaded or unwound or unwinded.
in response to rotation of the belt reel to ng direction, the second axial end of the torsion bar locks against rotation in the delivery direction relative to the frame.

[0004] Preferably, a block mechanism that is sensitive to a vehicle or sensitive to changes in a vehicle running state, and the locking device are
While substantially locking the second axial end of the torsion bar,
And a disabling device for disabling or disabling the vehicle sensing block mechanism. The vehicle sensing block mechanism includes an inertial sensor and a control disc for cooperating with the sensor, the control disc being coupled for rotation with the belt reel via a torque limiting coupling or coupling. Are combined.

In the retractor of the present invention, after the belt tensioning operation, the torsion bar can reversely rotate the belt reel by a rotation angle that is more than adequate or sufficient for energy conversion. A torsion bar made of a suitable grade or grade of steel can be twisted more than 360 degrees between the two axial ends of the torsion bar. Due to the torque limiting connection or coupling, the control disc is separated or released from the connection with the belt reel under a certain load, so that the control disc blocked by the vehicle-sensing sensor is destroyed by the belt reel rotating in the unwinding direction. Without maintaining the proper functioning of the vehicle-sensing locking mechanism.

According to another aspect of the present invention, the belt pretension drive includes a pulley, a cable that engages an outer periphery of the pulley, and a connecting disc that is connected to the pulley for rotation therewith. A drive having at least one connecting pawl mounted on the connecting disc so as to be deflectable or displaceable, and a connecting tooth connected to the second shaft end of the torsion bar and selectively engaged by the connecting pawl. And gears. After the belt pretensioning operation is completed and finally the energy conversion by twisting the torsion bar, the coupling pawl is disengaged (disengaged) from the drive gear, thus allowing the belt reel to move freely within the frame. It can rotate and the vehicle sensing block function is fully restored.

[0007]

Further features and advantages of the invention will become apparent from the description of several embodiments of the invention and the referenced drawings.

In the embodiment of the retractor belt and tensioner shown in FIGS. 1-5, the belt reel 1
2 are rotatably mounted between the arms of the load bearing frame 10. Belt reel 12 and belt belt 14
It is used to wind up.

On the left side of the frame 10 as shown in FIG. 1, an actuator mechanism for blocking the belt reel is provided, and on the left side of the frame 10, a retractor spring (not shown) is provided on the belt reel 12. The belt retractor 12 is loaded in the belt retracting direction by engaging with the end of the belt retractor 12. The block pawl 16 is a vehicle controller and / or an automobile control device which will be described in detail below.
The belt retractor 1 is controlled by the belt detection control device.
The rotation of the belt reel 12 in the belt rewinding direction is blocked by engaging with the block teeth 11 in 2.

On the right side of the frame 10, the functional components necessary for the belt tensioning function and the subsequent energy conversion function are also provided.

This part includes a cable 18 under tension when the belt tension drive is released, an inertial mass, and a preloaded spring and the like, for example by a linear piston / cylinder drive by pyrotechnics. Things are included. The cable 18 engages the circumference of the pulley 20 and is wrapped around it at least once. The pulley 20 has a first ratchet gear 22 drivingly connected thereto.
Is disposed on the first cylindrical boss.

The ratchet gear 22 has four swivel pawls 24 spaced along its outer circumference. The pawls 24 are offset by 90 degree pitch and are paired offset by half the tooth pitch, making the coupling engagement reliable. A leaf spring 28 is provided to push the pawl radially inward with respect to the ratchet gear 22.
Are mounted on the disk 26, so that the pawl can only pivot outwards when the spring force is exceeded.
The disk 26 is arranged concentrically on the ratchet gear 22.

The first ratchet gear 22 is provided at the end of the torsion bar 30 facing the belt tensioner.
It is rotatably mounted and the torsion bar is concentrically arranged in the belt reel 22.

The second ratchet gear 32 is integrally formed with the cylindrical drive wheel 32a holding the first ratchet gear 22 by the internal connecting teeth engaging with the first ratchet gear 22. With this ratchet gear, the second ratchet gear is positively interlocked with the torsion bar 30 and is concentrically located around the torsion bar 30.

The pawls 24 are pivotally mounted on the outer periphery of the first ratchet gear 22, which are directed outward when the first ratchet gear 22, and therefore the pulley 20 directly connected thereto, rotates at a particular angular acceleration. It pivots and engages the internal connecting teeth of the second ratchet gear 32, thus connecting the pulley 20 to the belt reel 12 via the ratchet gears 22, 32 and the torsion bar 30.

The second ratchet gear 32 is provided with four claws 34 on its outer circumference, which are pressed radially inward by a leaf spring 38. These claws 34 are offset like the claws 24. The leaf spring 38 is provided on a disk arranged concentrically with the ratchet gear 32.

A ring 40 having internal connecting teeth is provided around the second ratchet gear 32 so as to surround the second ratchet gear 32.
The ring 40 is mounted in a bearing member 10a connected to the frame 10. The internal connecting teeth and the pawls 34 are engaged with the internal connecting teeth of the ring 40 by the load of the leaf spring 38 at a specific angular acceleration in the tension direction of the torsion bar 30, and thus the belt webbing of the second ratchet gear 32. It is formed to fit.

The ring 40 is provided with a control cam 42 on its side facing the frame 10, which engages the blocking pawl 16 in the tension direction of the belt webbing when the ring 40 rotates. The pawl is moved downward to the inoperative position, thereby disabling the locking mechanism.

A stopper portion 4 is provided on the outer peripheral surface of the ring 40.
4 are provided. The frame 10 is provided with a stopper 46 facing the stopper 44 on the side facing the belt tension portion. A compression spring 48 is provided between the stoppers 44 and 46, whereby the ring 40
Is preloaded away from the stopper 46. When coupled to the second ratchet gear 32 in the ring 40, the ring is rotated against the force of the compression spring 48 until the stopper 44 hits the stopper 46 and further rotation of the ring 40 is blocked. . The shaft end of the torsion bar 30 remote from the belt tensioner is provided with a knurled head 50 which is inserted into a suitably shaped recess 52 in the belt reel 12 for positive action. Mutual lock to. The belt reel 12 is mainly
It has two side flanges 12a, 12b and a substantially hollow cylindrical sleeve 12c, which is a groove (not shown) for the belt web 14 to be wound onto the belt reel 12 to pass through. have. Torsion bar 30
Penetrates the hollow cylindrical inside of the sleeve 12c of the belt reel. The end portion of the belt web 14 is a torsion bar 30.
Form a loop located at. The torsion bar 30 is rotationally connected to the belt reel 12 by means of a notched head. In the idling state,
The pawls 24 and 34 of the ratchet gears 22 and 32 are disengaged from the internal linking teeth facing each other, thus allowing the belt reel 12 to rotate freely with the torsion bar 30.

The belt reel 12 is provided with a protrusion 60 having a spur gear 62 on the side remote from the belt tension drive device. A control disk 64 is mounted on a hub 66 on the protrusion 60 of the belt reel 12 acting as a shaft, so that the belt reel 12 and the protrusion 60
Engage with end teeth 68 located at the ends facing each of the and to match end teeth 62 of protrusion 60. The control disc 64 is axially displaceable with respect to the projection 60 and can be separated from the mutually facing end teeth 62 and 68, so that the control disc 64 is provided with the belt reel 12.
Can rotate freely with respect to. This is shown very simply in FIG. 2 for a better overview.

On the outer periphery of the control disk 64, control teeth 69 for an activation mechanism for detecting a vehicle are provided. An inertial disc 70 is rotatably mounted on the control disc 64, and its rotation is limited to a predetermined angular range. The control teeth 69 of the control disc 64 interact in a known manner with a vehicle-sensing actuating mechanism, which is indicated by the reference numeral 71 and is pivotally mounted by placing a ball overlap on the housing 10. It has a starting claw 75. The blocking pawl 16 (see FIG. 1) can be actuated in a known manner and by means of a control disc by interacting with the blocking teeth 11 on the flanges 12a, 12b of the belt reel 12.

A pin 74 is pushed into a predetermined position in an axial recess 72 of the protrusion 60. This pin 74
Is provided with an enlarged end 76, which acts as a contact surface for a spring 78. The spring 78 contacts the end surface 66 of the control disc 64 and axially urges the control disc 64 toward the end groove 62 of the protrusion 60. End teeth 62 and 68 as well as by pins 74 and springs 78.
Thus, a torque limiting connection is formed between the control disc 64 and the belt reel 12.

When the belt tensioner is actuated, the cable 22 exerts a torque on the outer circumference of the pulley 20 in a known manner. As a result of the rotation of the pulley 20, the pawls 24 of the ratchet gear 22 move to mesh with the internal connecting teeth of the ratchet gear 32, and thus the pulley 20, ratchet gear 22, ratchet gear 32, and torsion bar 30. And are connected together firmly. The rotation of the pulley 20 is transmitted to the belt reel 12 by the torsion bar 30. The belt reel is driven in the belt retracting direction, so that the seat belt device does not loosen the belt. Upon completion of the belt tensioning action, the two ratchet gears 22 and 32 remain connected together, and thus the torsion bar 30 also remains connected to the pulley 20.

When the belt tensioning action is completed, the passengers of the vehicle move forward, and the belt web 14 moves to the belt reel 1.
Drawn from 2. Belt reel 12 and torsion bar 30
And the second ratchet gear 32 is the first ratchet gear 2
Rotate in the belt pull-out direction together with 2.

When the angular acceleration is sufficiently large, the pawl 34 of the second ratchet gear 32 overcomes the force of the leaf spring 38 and pivots outward to engage the internal connecting teeth of the ring 40. As a result, ring 40 overcomes the force of compression spring 48 and is rotated until stopper 44 of ring 40 hits stopper 46 of frame 10 to prevent further rotation of ring 40, thereby causing control cam 42 to rotate. Engages the block pawl 16 and moves it downwards to the inoperative position. At the same time, the belt reel 12 includes the torsion bar 30, the second ratchet gear 32, and the ring 40.
And the stopper 44 supported on the stopper 46 block in the belt withdrawing direction.

However, if a large load is generated in the seat belt device after the belt is tensioned, and a correspondingly large torque is applied with a tension of several KN via the belt web 14 on the belt reel 12. At the end, the resulting torsional action causes the torsion bar 30 to begin plastically deforming about its axis. As a result of this plastic deformation, energy is used up and the belt web 1
The peak load generated in No. 4 is largely absorbed. By appropriately defining and selecting the dimensions of the material, both the threshold at which the plastic deformation of the torsion bar 30 begins and the resulting damping effect behavior are set to virtually any extent. can do.

Since the block pawl 16 remains disengaged from the belt reel 12, the reel is free to rotate.

When the load applied to the belt web 14 is then released, the pawls 24 and 34 are disengaged from their corresponding connecting teeth by the spring force exerted by the leaf springs 28 and 38. Further, the ring 40 is a spring 38 (spring 48).
Is returned to its starting position by restoring the belt retract function as well as the vehicle sensing blocking function.

Even before the belt tensioner is actuated, the activation pawl 75 engages the control teeth 69 of the control disc 64. However, the control teeth 69 are shaped so that the control disc 64 together with the belt reel 12 can rotate in the direction of belt retraction. If the belt continues to rotate in the belt retracting direction, the control disk 64 cannot follow the rotation of the belt reel 12. Since the control disk 64 and the belt reel 12 are in the torque limiting connection state, the control disk 64 is disconnected from the belt reel 12 or the protrusion 60. Spring 78 between belt reel 12 and control disc 64
As soon as a specific torque value, defined by the geometry of the teeth 62, 68, is exceeded, an axial displacement of the control disk 64 will occur until the mutual engagement of the teeth 62 and 68 is disengaged. . In this way, the vehicle-sensing activation mechanism remains functional even when the belt is strained resulting in a conversion of energy.

FIG. 5 shows a different perspective view of the control disc 64, in which it can be clearly seen that the teeth 68 correspond to the teeth 62 of the projection 60.

FIG. 6 shows another embodiment of the present invention. Instead of the protrusion 60, a pivot pin 60 a having external teeth 80 is provided apart from the belt reel 12. A pivot pin 60a with external teeth 80 is inserted into a recess 82 in the belt reel 12 with corresponding internal teeth 84 and is thus adapted to rotate with the belt reel 12. A control disk 64 is attached to the pivot pin 60a, as in the previous embodiment.

In FIG. 6, a portion of the belt and a vehicle-sensing locking mechanism are shown. A control ring 88 is rotatably mounted on the outside of the frame 10. The control ring 88 is provided with internal teeth 90 to allow the locking pawl 5
It is rotatably mounted by known means to actuate the zero. Inner teeth 90 interact with control pawls (not shown) on control disc 64 to connect or couple control disc 64 to control ring 88 when inertial disc 70 is rotated relative to control disc 64. The belt reel 12 is locked. In this embodiment, inertial disc 70 is attached to hub 66 of control disc 64. The vehicle detection sensor 71a has an actuating claw 75a located on the inertial ball 73a, and functions on the same principle as the sensor 71.

In FIGS. 7 to 9, the belt reel 1
Another embodiment of a torque limiting connection between the two and the control disc 64 is shown. The protrusion 60 differs from the previous embodiment in that it is provided with external teeth 92 and the control disc 64
The tooth is also shaped in relation to it. The three swivel pawls 94, 96, 98 have teeth 10 on their inner surfaces.
0 are provided, which correspond appropriately with the external teeth 92 of the projection 60. The pawls 94, 96, 98 are supple and are pretensioned inward to engage the outer teeth 92 of the protrusion 60. However, if the force acting in the radial direction exceeds the spring force of the claws 94 to 98, the claws 94 to 98
Are moved substantially radially outward with respect to the control disc 64, and thus disengage the control disc 64 from engagement with the belt reel 12.

Another effect is obtained by the torque limiting connection. When the belt tensioner connected to the belt reel 12 is operated, the belt reel 12 is strongly accelerated in the direction opposite to the belt retracting direction. Today, stronger gas generators are used to more effectively eliminate belt slack. The coupling of the inertial disk 70 which activates the belt-sensing locking mechanism is about 0.5.
Designed for G to 2G angular acceleration. However, during belt tension, there is a risk that the actuating device of the locking mechanism will be damaged as a result of the greater angular acceleration, especially when a powerful gas generator is employed. Due to the torque limiting connection in both directions of rotation, the control disc 64 is separated from the belt reel 12 by simple means, even at the beginning of belt tensioning, thus maintaining the proper functioning of the starter under all circumstances. Can continue to do.

[Brief description of drawings]

FIG. 1 is an exploded or exploded perspective view of a first embodiment of a belt retractor and a belt tensioner in which a functional portion for operating a lock mechanism is omitted.

FIG. 2 is an axial sectional view of the belt retractor shown in FIG.

3 is a sectional view taken along the line III-III in FIG.

FIG. 4 is an exploded view showing a belt retractor of the present invention in a greatly simplified manner, showing a functional portion for operating a lock mechanism.

FIG. 5 is an exploded perspective view of a control disk.

FIG. 6 is an exploded perspective view of a second embodiment of the belt retractor showing functional parts for input control of the locking mechanism shown in the partially exploded view.

FIG. 7 is an exploded or exploded perspective view showing a third embodiment of the belt retractor, showing a functional portion for operating the lock mechanism of the present invention, in a greatly simplified manner.

8 is a front view showing the control disk of the embodiment of the present invention shown in FIG. 7 in a greatly simplified manner.

FIG. 9 is a perspective view showing the control disk of the embodiment of the present invention shown in FIG. 7 in a greatly simplified manner.

[Explanation of symbols]

 10 frame 11 block tooth 12 belt reel 16 block claw 18 cable 20 pulley 22 connecting disc 24 connecting claw 30 torsion bar 34,40 locking device 42 holding member 64 control disc 62,68 tooth 73a, 75a inertial sensor 96 connecting claw

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Volker Holzafell San Wentel, Klottenbacherstraße 23, Federal Republic of Germany 23 (72) Inventor Albrecht Mueller, Dürlangen, Ekendorffeg 3 (72) Inventor Gunther Weimueller Germany Federal Republic of Voldersteinenberg, Forststraße 4

Claims (11)

[Claims] 1. A seat belt retractor, a frame, a belt reel rotatably supported in the frame, a belt pretension drive device for rotating the belt reel in a belt winding direction, and A torsion bar (30) having a first shaft end connected to a belt reel (12) and a second shaft end engaged by the belt pretension drive (20), the belt pretension drive (2)
0), the second shaft end of the torsion bar (30) rotates in the delivery direction with respect to the frame (10) in response to the rotation of the belt reel (12) in the belt delivery direction. Locking device (34, 4)
0) and a seat belt retractor. 2. The seat belt retractor according to claim 1, wherein the vehicle sensing block mechanism (16) and the locking device (34, 40) comprise the torsion bar (30).
And a disabling device (42) for disabling the vehicle sensing blocking mechanism (16) while substantially locking the second axle end of the seat belt retractor. 3. The seat belt retractor according to claim 2, wherein a block pawl (16) for engaging the vehicle sensing block mechanism with the belt reel (12).
The disabling device has the block claw (16)
Seat belt retractor having a holding member (42) for holding the vehicle in a position where the engagement with the belt reel (12) is released. 4. The seat belt retractor according to claim 2, wherein the vehicle sensing block mechanism comprises an inertial sensor (73a, 75a) and a control disc (64) for cooperating with the sensor. , The control disk (64) is a torque limiting connection (60, 62, 68, 7).
4, 78; 92-106) and a seat belt retractor which is connected to rotate with the belt reel (12). 5. The seat belt retractor according to claim 4, wherein the torque limiting connection is formed on the control disc (64) and the belt reel (12) with elastically interengaged teeth (62). , 68). 6. The seat belt retractor according to claim 5, wherein the control disk (64) is axially movable with respect to the belt reel (12). 7. The seat belt retractor according to claim 4, wherein the torque limiting connection is at least one connecting pawl (96) on one of the belt reel (12) and the control disc (64). And a tooth (92) on the other side, and the connecting claw (96) has the tooth (96).
a seat belt retractor elastically engaged and retained with a). 8. The seatbelt retractor according to claim 1, wherein the belt pretension drive together with a pulley (20) and a cable (18) engaging an outer periphery of the pulley (20). A connecting disc (22) rotatably connected to the pulley (20), at least one connecting pawl (24) deflectably mounted on the connecting disc (22), and the torsion bar (30)
Drive gear (32) having connecting teeth connected to the second shaft end of the and selectively engaged by said connecting pawl (24)
Seat belt retractor with and. 9. A seat belt retractor according to claim 8, wherein said drive gear (32) has at least one locking pawl (34) and said locking device limits rotation of said frame (10). A seatbelt retractor having a ring member (40) mounted on the wheel and provided with locking teeth for selectively engaging the locking pawl (34). 10. The seat belt retractor according to claim 9, further comprising an automatic sensing block mechanism having block claws (16) selectively engaged with block teeth (11) of the belt reel (12). The ring member (4
0) A seat belt retractor provided with a holding member (42) for holding the block claw (16) in a position where the block claw (16) is disengaged from the block tooth (11). 11. The seatbelt retractor according to claim 1, wherein the belt reel (12) is hollow and the torsion bar (3).
Seat belt retractor 0) is housed concentrically in the belt reel (12).